1. Technical Field
Systems and methods presented herein generally relate to power converters and more specifically to gated energy power converters.
2. Discussion of the Related Art
Compact and efficient power supplies are often desired by electronics manufacturers for a variety of reasons (e.g., to decrease device size and to improve power consumption). Pulse-width-modulated switching power supplies offer such compactness and efficiency in a number of different topologies, such as transformer-coupled switching power supplies (e.g., a flyback converter) and direct-coupled switching power supplies (e.g., buck or boost switching power converters). In a transformer-coupled power supply, the power output is isolated from the power input through a transformer, whereas the power output is not isolated from the power input in a direct-coupled switching power supply.
Pulse-width-modulated switching power supplies generally often employ a pulse width modulator (“PWM”) that controls a duty cycle of power pulses. For example, a boost switching power supply may include a switch coupled to an inductor that provides electrical energy to the inductor and a capacitor that outputs electrical energy from the inductor. A pulse-width modulator adjusts the duty cycle of the switch in response to sensing an output voltage at the capacitor. The inductor receives energy when the switch is closed and transfers it to the capacitor when the switch is open. A relatively large capacitor maintains a substantially constant output during the second half of the duty cycle (e.g., when the switch is open). The “on-time” of the switch thus defines a power cycle (e.g., when the switch is closed and electrical energy is transferred to the capacitor). In a flyback converter, the pulse-width modulator again adjusts the duty cycle of the switch in response to sensing an output voltage at the capacitor. However, energy is stored in a transformer primary winding of the flyback converter during the first half of the duty cycle and transferred to the transformer secondary winder, and thus the load, during the second half of the duty cycle. In both cases, the output voltage is regulated because the PWM determines the rate at which electrical energy is delivered at the output of the converter.